Inhaled Cannabis Relieved Neuropathic Pain in Diabetes

(HealthDay News) — A small trial shows a dose-dependent reduction in peripheral neuropathic pain with inhaled cannabis in patients with diabetes, according to a study published in The Journal of Pain.

Mark S. Wallace, MD, from the University of California in San Diego, and colleagues conducted a randomized trial in 16 patients with painful diabetic peripheral neuropathy. They examined the short-term efficacy and tolerability of inhaled cannabis; each participant was exposed to four single dosing sessions of placebo or to low, medium or high doses of cannabis in a crossover design.

The researchers performed baseline spontaneous pain, evoked pain and cognitive testing. Subjects were administered aerosolized cannabis or placebo and the pain intensity and subjective "highness" score was measured during the first hour and for an additional 3 hours.

Spontaneous pain scores were significantly different between doses (P<.001), the researchers found. Comparisons between placebo and low, medium and high doses were significant (P=.031, .04 and <.001, respectively), as were those between high vs. low and medium doses (both P<.001).

The high dose had a significant effect on foam brush and von Frey evoked pain (P<.001). The high dose had a significant negative effect (impaired performance) on two of the three neuropsychological tests.

"This adds preliminary evidence to support further research on the efficacy of the cannabinoids in neuropathic pain," the researchers wrote.